The present invention relates to a rotary internal combustion engine, and more particularly to an internal combustion engine that has simplified peripheral mechanisms and reduced volume while it has increased thermal efficiency and enhanced power output.
In a conventional four-stroke reciprocating internal combustion engine, one single cylinder and a piston therein together define a space in which the piston moves forward or backward in rectilinear motions. And, the cylinder is provided at top portion with intake and exhaust valves to timely open or close. Each work cycle includes four strokes, namely, induction, compression, explosion, and exhaust. For an ordinary auto engine, four of such conventional internal combustion engines (cylinders) are needed to drive a car. As shown in FIGS. 1A to 1D, the conventional internal combustion engine has a piston 10 which moves forward and backward to rotate a crank 12 via a connecting rod 11, so that power is output via a crank shaft 13. In FIG. 1A, the conventional internal combustion engine is in an intake state. In this state, the piston 10 moves downward, the intake valve 14 opens and the exhaust valve 15 closes, so that air is induced into the cylinder 16. In FIG. 1B, the conventional internal combustion engine is in a compression state. In this state, the piston 10 moves upward, both the intake valve 14 and the exhaust valve 15 are closed, so that air and fuel mixture in the cylinder 16 is compressed. In FIG. 1C, the internal combustion engine is in an explosion state. In this state, the intake valve 14 and the exhaust valve 15 are still closed. A plug 17 is ignited to cause the air and fuel mixture to explode in the cylinder 16 and thereby pushes the piston 10 downward. At this point, a power is generated to drive the crank 12 to move. In FIG. 1D, the internal combustion engine is in an exhaust state. In this state, the piston 10 moves upward, the intake valve 14 closes and the exhaust valve 15 opens, so that exhaust produced after explosion and combustion is discharged from the cylinder 16 via the exhaust valve 15. In the above four strokes of induction, compression, explosion and exhaust, each stroke causes the crank shaft 13 to turn 180 degrees (that is, one half circle). The four strokes together cause the crank shaft 13 to turn total 720 degrees (that is, two circles). Only the turning of 180 degrees of the crank shaft 13 in the explosion stroke generates driving power. And, in the explosion stroke, the reciprocating rectilinear motions of the piston 10 is converted into circular motions only via the crank 12. That is, power can be most effectively output in a tangential direction only when the crank 12 is in a 90-degree position. Therefore, the conventional internal combustion engine has only limited working efficiency due to its structure, and power generated by the burned and exploded gas can not be fully utilized.
To maintain continuous output of power and to balance vibration during operation, the conventional four-stroke reciprocating internal combustion engine requires multiple cylinders, and therefore, it has increased volume and weight. Moreover, to enable the intake and the exhaust valves at the top of the cylinder to timely open and close during the operation of the internal combustion engine, other components, such as rotating shafts, cams, time control means (cogged belt), are needed and therefore make the conventional internal combustion engine have very complicate peripheral mechanisms. These complicate peripheral mechanisms also consume a part of power to work and therefore further reduce the thermal efficiency of the internal combustion engine.